System for coupling host computer meanswith base transceiver units on a local area network

ABSTRACT

Improved apparatus for a radio communication system having a multiplicity of mobile transceiver units selectively in communication with a plurality of base transceiver units which communicate with one or two host computers for storage and manipulation of data collected by bar code scanners or other collection means associated with the mobile transceiver units. A network controller provides selective interface means to be employed between the host computers and the base transceivers whereby low data rate base transceivers may be utilized with the network controller while spread spectrum or high data rate networked base transceivers may be also utilized. The network controller may allow selection of interface means for three of its ports from its front panel with use of three input keys. The network controller is entirely external to the host computer or computers, and can couple to a variety of commonly encountered host ports. Most preferable one- or two-network controller ports can each be software configured to match any needed host port, so that the host computer(s) need not be adapted to a radio network protocol accommodating the multiple base transceiver units.

CROSS-REFERENCE TO RELATED APPLICATIONS

This case is a continuation of application Ser. No. 08/277,944, filedJun. 29, 1994 which is a continuation of application Ser. No.08/057,218, filed on May 4, 1993 and abandoned, which is a continuationof application Ser. No. 07/700,704, filed May 14, 1991 and abandoned.

BACKGROUND OF THE INVENTION

The present invention in a preferred implementation relates toimprovements in radio data communication systems wherein a number ofmobile transceiver units are to transmit data to a number of basestations under a wide range of operating conditions. The invention ispreferably to be applicable as an upgrade of an existing data capturesystem wherein a number of hand-held transceiver units of an earlierdesign are already in the field representing a substantial economicinvestment in comparison to the cost of base stations, accessories andcomponents. In installations spread over an extensive area, a largenumber of mobile portable transceiver units may be employed to gatherdata in various places and multiple base stations may be required. In avariety of such installations such as warehouse facilities, distributioncenters, and retail establishments, it may be advantageous to utilizenot only multiple bases capable of communication with a single host, butwith multiple hosts as well.

An early RF data collection system is shown in Marvin L. Sojka, U.S.Pat. No. 4,924,462 assigned to the assignee of the present application.This patent illustrates (in the sixth figure) a NORAND® RC2250 NetworkController which supports one base transceiver for communication withmultiple mobile portable transceivers. The exemplary prior art device iscapable of communicating with a host computer through an RS232Cinterface at up to 19,200 baud in asynchronous mode. In order for anoptional RS422 interface to be substituted for an RS232C interface, theunit must be opened and substitute circuitry components installed withinit.

SUMMARY OF THE INVENTION

The present invention provides an improved network controller to serveas a consolidation link between one or more host computers and one ormore base transceiver units, each of which may be communicative withmany mobile portable transceiver units being moved about a warehousecomplex for the collection of data. The network controller inventionprovides a front panel display with three operator-available controlkeys for selections of function and up or down scrolling through choicesprovided on the front panel display.

The invention will allow incorporation with existing base transceiversas well as with high-speed spread spectrum and synthesized radionetworks at the same time. The invention allows the creation of a radiocommunication system with multiple host devices using differingcommunication protocols. Higher speed host device interfaces may be usedas a result of the inclusion of the invention in an existing radiocommunication system. The invention provides means for the coupling oflarge networks of serially interconnected base transceivers over asingle twisted pair of wires.

The invention provides a plurality of communication ports forinterconnection to one or more host computers and one or more basetransceiver systems or units. The communication ports available forconnection with the host computers may be configured to provideselective interfaces without any requirement for rewiring or otherhardware modification. A first port of the controller may be selected tointerface with a host computer by either RS232 or V.35 means. Theselection of interface means may be performed by the end user withchoices made on the front panel control keys of the device.

A second port of the invention may be selected to provide interfacemeans by a choice of RS232, RS422, or RS485 means or through a NORAND®Radio One Node Network proprietary interface. This second port may becommunicative with a second host computer or with existing installedbase units when RS232 means are selected, or with existing base unitswhen RS422 means are selected. In addition, the second port may beconfigured to communicate with a network of new generation base units,either by RS485 interface protocol, or by the NORAND® Radio One NodeNetwork proprietary interface.

The third port of the invention, like the second port hereof, may beselectively configured to communicate by RS232, RS422, RS485 or NORAND®Radio One Node Network proprietary interface means. For both the secondand third ports, as well as for the host port, configuration of the portis accomplished by selection of the port on the front panel of theinvention controller with the select key and then selection of thedesired interface configuration through appropriate use of the up anddown keys to scroll to the correct means to be selected. Because theinvention permits internal, software-controlled, selection of thedesired interface means for each port, the end user may easily selfconfigure the unit for a particular use, thereby providing a highlyversatile device. In addition the configuration choice means issimplified for the user, because the choices are conveniently displayedon the front panel display and a choice can be made from a scrollablelist.

The introduction of the selectable RS485 interface in the presentinvention enables the controller to be interfaced to a network of newgeneration base station units which may comprise several basetransceiver units configured on a single network circuit.

The inclusion of the selectable NORAND® Radio One Node Networkproprietary interface means for the second and the third ports providesmeans for incorporation of new generation base transceiver units havingparticularized wiring and control requirements.

A diagnostic port configured for RS232 interface means is provided toprovide selective communication, either remotely through modem means, orthrough direct coupling, with diagnostic and reprogramming apparatus.

The invention is provided with an application specific integratedcircuit used in combination with a control processor unit capable of aspeed of 16.667 mhz with direct memory access functionality available atits communication ports. Internal memory components to be coupled to thecentral processor unit and application specific integrated circuit willcomprise nonvolatile electrically eraseable programmable read onlymemory elements, dynamic random access memory elements, and nonvolatileFLASH memory elements which permit erasure by application of +12 VDC toprescribed pins.

Power supply means are supplied exteriorly to the invention in order tomake the invention standardized for United States, European and othercountries' local power company output characteristics.

It is therefore an object of the invention to provide a radiocommunication system which permits the interconnection of one or twohost computer devices to a multiplicity of base transceiver units whichmay include both prior art existing installed units and new generationunits capable of spread spectrum or synthesized radio transmission.

It is a further object of the invention to provide a radio communicationsystem network controller which may allow interconnection of amultiplicity of devices which are operating with non-uniform electricalinterface characteristics.

It is a further object of the invention to provide a radio communicationsystem network controller which may be configured for varying interfacerequirements by operation of a limited number of front panel keys.

It is a further object of the invention to provide a radio communicationsystem network controller which will allow utilization of single twistedpair networks of serially networked base transceiver units, each ofwhich being communicative with a large number of individual mobile datacollection transceiver units.

These are other objects of the invention will be apparent fromexamination of the detailed description which follows.

DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 is a block diagram of the prior art data communication system.

FIG. 2 is perspective view of the invention.

FIG. 3 is a schematic representation of an exemplary radio communicationsystem utilizing the invention.

FIG. 4 is a diagrammatic illustration of the control circuitry elementsof the invention.

FIG. 5 is a rear elevation view of the invention.

FIG. 6 is a diagrammatic illustration of the application specificintegrated circuit of the invention.

FIG. 7 is a bock diagram showing an exemplary implementation ofintelligent network and router transceiver units such as the networktransceiver units of FIG. 3.

FIG. 8 is a diagram of an RF system utilizing a network controlleraccording to FIGS. 2-6, with one of its network ports configured forcommunication with a second host, and another of its ports coupled witha multiplicity of RF transceivers via an adapter unit.

FIG. 9 is a diagram illustrating the use of two network controllersaccording to FIGS. 2-6, configured for dual host computers each, andhaving their relatively high data rate extended distance network portscoupled with a multiplicity of intelligent network and routertransceiver units implemented according to FIG. 7.

FIG. 10 is a diagram similar to FIG. 9 but showing the pair of couplednetwork controllers interfaced to a common relatively high data ratesystem having multiple hosts (e.g.) a local area network of the Ethernettype or equivalent e.g. fiber optic type).

FIG. 11 is a diagram similar to FIG. 10 but indicating the networkcontrollers being coupled to respective different high data ratemultiple host systems (e.g. token ring type local area networks or otherindividual networks e.g. fiber optic loop networks of thecollision-sense multiple-access type).

FIG. 12 is a view similar to FIG. 9 but intended to diagrammaticallyindicate a distribution of network and router transceivers and otherelements of an on-line RF data collection system over an extensive areaof a facility e.g. of one of the types previously mentioned.

FIG. 13 shows an intelligent integrated controller and radio base unitwhich unifies controller and radio components such as shown in FIG. 7into a single housing of the size represented in FIGS. 2 and 5.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows an existing radio frequency data transmission system 10wherein a base station transceiver means 11 has a number of mobiletransceiver units such as 12A, 12B, . . . , 12N in radio communicationtherewith.

By way of example, the base station may be comprised of a radio baseunit 14 such as the model RB3021 of Norand Corporation, Cedar Rapids,Iowa, which forms part of a product family known as the RT3210 system.In this case, the radio base 14 may receive data from the respectivemobile RF terminals, e.g. of type RT3210, and transmit the received datavia a network controller and a communications link 16 (e.g. utilizing anRS-232 format) to a host computer 17.

The data capture terminals 12A, 12B, . . . , 12N may each be providedwith a keyboard such as 18, a display as at 19, and a bar code scanningcapability, e.g. via an instant bar code reader such as shown in U.S.Pat. No. 4,766,300 issued Aug. 23, 1988 and known commercially as the20/20 High Performance Bar Code Reader of Norand Corporation.

FIG. 2 provides a perspective view of the invention 40 in the preferredembodiment case 20. Front panel 22 is provided with display 24 andselect key 26, up key 28 and down key 30. Power indicator 32 comprises alow power green light emitting diode which is energized when power issupplied to the invention 10. Error condition indicator 34 is a yellowLED which is software controlled to be energized if the invention 10 isin error condition.

FIG. 3 discloses a diagrammatic illustration of a radio communicationsystem in accordance with the present invention. Invention networkcontroller 40 is coupled to host computer 42 such that data may beinterchanged between the devices over host communications link 44, whichmay be either in an RS232C format or selectively in an RS422 format. Thehost communication link 44 couples to controller 40 at host port 46.

First communication port 48 of controller 40 provides means for couplingof network 50 to controller 40. Network 50 comprises a number of base RFtransceiver units 52A, 52B and 53B, each of which may be selectivelyemployed in the radio frequency communication of data from mobiletransceiver units. It is to be understood that base transceiver units 52are designed and equipped to be operable in the exchange of data withnetwork controller 40 over network link 56 such that each basetransceiver unit 52A, 52B, or 53C may independently exchange data withnetwork controller 40 through first communication port 48. When firstcommunication port 48 is intended for operation with a network such asnetwork 50 of base transceiver units 52A, 52B and 53C, for example,network controller 40 is selectively operated to provide an RS485interface at first communication port 48. First communication port 48may be alternately selected to operate as an RS232C interface, as anRS422 interface, as a proprietary NORAND® Radio One Node Networkinterface or as a high speed V.35 interface. The selection of interfaceto be provided at first communication port 48 is front panel controlled,that is, the user may operate front panel keys 28, 30 and 26 (See FIG.2) to direct the proper interface to be provided at first communicationport 48.

Base transceiver units 52A, 52B, and 52C are coupled to network link 56by serial means, rather than parallel means, and each may be caused totransmit or to receive independently from the others while additionallybeing communicative with network controller 40 in a randomly chosenfashion.

It is further to be understood that interface translation is providedwithin controller 40 such that data communicated at first communicationport 48 may be directed to host 42 at port 46 via properly choseninterface means as is required by the host 42 with which communicationis intended.

Like first communication port 48, second communication port 57 may beinternally switched among interface choices of these types: RS232C,RS422, V.35, RS485 and proprietary NORAND® Radio One Node Networkinterface. In the illustrated arrangement of FIG. 3, for example, secondcommunication port 57 is coupled over third link 53 to previouslyinstalled base transceiver 54, which heretofore had been used in a priorart system as is illustrated in FIG. 1. Because of limitations of basetransceiver 54, it must communicate via RS232C interface format andtherefore, second communication port 57 must be selected to operate inRS232C interface mode. However, when second communication port 57 isdesired to communicate with a network via RS485 interface, front panelkeys 26, 28 and 30 may be manipulated by the user to provide the RS485interface availability at second communication port 57. Likewise, secondcommunication port 57 may be selected to operate as an RS422interface,as a V.35 interface, or as the proprietary NORAND® Radio One NodeNetwork interface.

Diagnostic port 55 provides a fourth communication pathway for networkcontroller 40, providing an asynchronous port operable at 300 to 19,200baud as an RS232C interface. When desirable, diagnostic port 55 may becoupled by diagnostic link 58 to diagnostic device 60 for purposes oferror diagnosis of controller 40 by diagnostic device 60, or forreprogramming of memory devices within controller 40 when desired. It iscontemplated that diagnostic device 60 comprises a 16-bit microprocessorcommonly known as a personal computer or "PC". The mode of couplingbetween diagnostic device 60 and network controller 40 may be direct orthrough remote means by use of a modem.

Referring now to FIG. 4, a central processing unit 70 is provided withat least four data communication ports, illustrated at numerals 71, 72,73, and 74. First data communication port 71 may be selectively coupledto RS232 interface member 76 or V.35 interface member 78. The choice ofwhether RS232 interface member 76 or V.35 interface member 78 is chosenis dependent upon the operating characteristics presented by the hostcomputer, such as host computer 42 of FIG. 3, with which networkcontroller 40 will communicate. The choice of whether firstcommunication port 71 is coupled to interface member 76 or to interfacemember 78 depends on the front panel selection made by the user by keys26, 28, and 30 shown in FIG. 2.

Second communication port 72 may be selectively coupled to RS232 member80 or to RS485 interface member 82 or to RS422 interface member 84 or toNORAND® Radio One Node Network proprietary interface member 86. By useof front panel keys 26, 28, and 30 of FIG. 2, the user may select secondcommunication port 72 to be coupled to any one of interface members 80,82, 84, and 86.

Third communication port 73 is identical to second communication, port72 in functionality, being selectively couplable to RS232 interfacemember 88, to RS485 interface member 90, to RS422 interface member 92 orto NORAND® Radio One Node Network proprietary interface member 94.

In the preferred embodiment of the invention 40, central processing unit70 of FIG. 4 comprises a Motorola™ 68302 integrated chip cooperativewith an application specific integrated circuit. Central processing unit70 employs novel features allowing the bidirectional use of a datacommunicative line of the Motorola™ 68302 chip and a single clock signalline to eliminate the need for coder-decoder members to be associatedwith the Motorola™ 68305 chip while allowing the use of only one pair ofsignal wires to be coupled to the RS485 interfaces 82 and 90 of FIG. 4.

Fourth communication port 74 of central processing unit is coupled toasynchonous RS232 interface member 97 to be available forinterconnection of a diagnostic device therewith.

Also coupled to central processing unit 70 are display member 24 andkeyboard member 31 with which keys 26, 28, and 30 of front panel 22(FIG. 2) are interactive.

Memory elements including EPROM element 96, DRAM unit 98, FLASH memoryunit 100 and EEPROM element 102 are intercoupled with each other andwith central processing unit 70.

Power supply member 104 is selectively attachable to invention networkcontroller 40. In order to avoid the necessity of different models ofnetwork controller 40 depending on the local electrical power utility'soperating characteristics, power supply 104 is provided in optionalmodels depending on the country in which it is to be used, power supply104 being capable of providing satisfactory output power to networkcontroller 40 regardless of the voltage or frequency of the input sourceprovided to power supply 104.

The application specific integrated circuit (ASIC) used in the inventionnetwork controller 40 is disclosed in FIG. 6 and is identified by thenumeral 120. ASIC 120 comprises a central processor unit interface 122member which is coupled to the central processor unit bus by CPU buslink 124 which extends from ASIC 120. Also coupled to the CPU bus link124 is dynamic random access memory (DRAM) timing element 126, whichprovides network controller 40 with timing signals for the DRAM member98 illustrated in FIG. 4 when memory refresh of the DRAM 98 isindicated. DRAM timing element 126 is also coupled exteriorly to theASIC 120 to DRAM member 98 by DRAM link 127.

Central processing unit interface 122 is coupled to asynchronous signalprocessing element 128 by signal path 130. Asynchronous signalprocessing element 128 comprises a baud rate generator cooperative witha universal asynchronous receiver-transmitter.

Also coupled to central processing unit interface 122 is network clockand control member 132 which comprises a programmable network clockgenerator which can be selectively programmed to generate an optionalclock speed for a network to be coupled through RS485 interfaces 82 and90 seen in FIG. 4. Network clock and control member 132 also providesdetection means for detections of failure conditions on a linked networkand provides control signals to system components in response thereto,including interrupt signals to programmable interrupt coordinatorcircuity included in central processing interface 122. Network clock andcontroller member 132 provides data encoding by the FM0 standard, thenthe encoded data may be operated upon by RS485 interfaces 82 and 84 andtransmitted and received by single twisted pair means to multipleserially networked base transceiver units exemplified by basetransceiver units 52A, 52B, and 52C illustrated in FIG. 3.

Keyboard controller element 134 is coupled to central processing unitinterface and provides a link exterior to ASIC 120 to keyboard 31 (SeeFIG. 3).

FLASH memory/EEPROM logic control member 136 is coupled to centralprocessing unit interface 122 and comprises control functions for FLASHmemory element 100 and EEPROM memory element 102 of FIG. 3.

Central processing unit interface 122 is also coupled by line 138 tolatches exterior to ASIC 120.

It is to be understood that the base transceiver units 52A, 52B, and 52Cillustrated in FIG. 3 are communicative with mobile transceiver units byelectromagnetic radio means. The mobile transceiver units may beassociated with bar code scanning devices such as the NORAND® 20/20 HighPerformance Bar Code Reader whereby the scanning devices scan an objecthaving a bar code associated therewith and collect information stored inthe bar code, which information is then transmitted through the mobiletransceiver units to base transceiver units such as base transceiverunits 52A, 52B, and 52C or base transceiver unit 54 of FIG. 3. The barcode data received by said base transceiver units is then transmitted,in the example of FIG. 3, over network 50 by base transceiver units 52A,52B, or 52C, or over link 53 by base transceiver unit 54, to networkcontroller 40 which performs the routing and delivery of the data to thestationary data processor, or processors, such as shown for example, byhost 42 of FIG. 3.

Description of FIGS. 7 through 11

FIG. 7 shows a block diagram of a particularly preferred intelligentbase transceiver unit known as the RB4000. It will be observed that thecomponents correspond with components of the network controller of FIG.4, and similar reference numerals (preceded by 7-) have been applied inFIG. 7. Thus, the significance of components 7-70 through 7-73, 7-76,7-82, 7-96, 7-98, 7-100 and 7-104 will be apparent from the precedingdescription with respect to FIG. 4 and 6, for example. I/O bus 700 maybe coupled with a spread spectrum transmission (SST) or ultra highfrequency (UHF) transceiver 701 which may correspond with any of thetransceivers of units 52A, 52B, 52C or 54 previously referred to. Thenetwork controller 70 could have a similar RF transceiver coupled withits data port 72 or 73 and controlled via input/output bus 400, e.g. fordirect RF coupling with router transceivers such as 901, 901, FIG. 9.

Referring to FIG. 8, a network controller 40 is shown with port 71configured for interface with a host port type SNA V.35 56K/64K bits persecond. Port 72 is shown as configured for communication with a personalcomputer of the PS/2 type operating asynchronously at 38.4K bits persecond. Port 74 is coupled with a modem 8-60 providing for remotediagnostics and reprogramming of the network controller 40.

Port 73 of network controller 40 is shown as being connected with anadapter component 801 known as the MBA3000. A specification for theMBA3000 is found in APPENDIX A following this detailed description. Inthe operating mode indicated in FIG. 8, the adapter 801 serves to couplecontroller 40 sequentially with four radio base transceiver units suchas indicated at 811 through 814. Component 811 is a commerciallyavailable radio base known as the RB3021 which utilizes features ofSojka U.S. Pat. No. 4,924,462 and of Mahany U.S. Pat. No. 4,910,794,both assigned to the present assignee, and the disclosures of which arehereby incorporated herein by reference in their entirety. Base station811 may communicate with a multiplicity of hand-held RF data terminalssuch as indicated at 821. Details concerning base transceiver units 812and 813, 814 are found in the attached APPENDICES B and C, respectively.Base 814 is indicated as being coupled with the adaptor 801 via RFbroadband modems 831 and 832. Base units 813 and 814 may communicatewith a variety of mobile transceiver units such as those indicated at833, 834 and 1001, the first two being particularly described inAPPENDICES D and E.

FIG. 9 shows two network controllers 40A and 40B each with its hostports configured as with the controller 40 of FIG. 8. In this example,the second ports 72 of the controllers 40A and 40B are configured forcommunication a relatively high data rate relatively along a distancenetwork channel 56 which may have the characteristics of the serialchannel 56 of FIG. 3, for example, an RS485 channel operating at 384kilobits per second (384K bps). Network base transceivers 52A, 52B and52C may correspond with the correspondingly numbered transceiver unitsof FIG. 3, for example, and the network may have additional networktransceivers such as 52D which may support communication with the radioterminal 1001 for example. Furthermore, the network transceivers mayhave RF coupling with router transceiver units such as indicated at 901,902 and 903. Router transceiver unit 902 is illustrated as a RB4000intelligent transceiver such as represented in FIG. 7 and having itsinput/output bus 700 coupled with a peripheral.

FIG. 10 is entirely similar to FIG. 9, for example, except that ports 72of the controllers 40A and 40B are coupled with separate serial typehigh data rate network channels, and ports 73 of the respective networkcontrollers are coupled to a very high speed network e.g. in the megabitper second range such as an Ethernet local area network 1000. Suitableinterfaces are indicated at 1001 and 1002.

FIG. 11 is entirely similar to FIG. 9 except that the ports 73 of thenetwork controllers 40A and 40B are coupled with respective local arearing type networks which may be separate from each other and each havetwo or more hosts such as represented in FIG. 9 associated with therespective ring networks such as token rings 1100A and 1100B. Suitableinterface means are indicated at 1101 and 1102.

Description of FIG. 12

FIG. 12 shows, for example, two network controllers 40A and 40B, eachwith two host computer units such as 42-1A. Host 42-2A is shown with aprinter or other peripheral P1 which may generate bar codes, forexample, for replacement of damaged bar codes or the like. Anotherprinter P2 is shown associated with base 52C, again for example, forproducing bar code labels where those are needed in the vicinity of abase station. In a large warehouse, relatively large distances may beinvolved for a worker to return to a printer such as P1 to obtain a newbar code label. Thus, it may be very advantageous to provide a printerP2 at the base station 52C which may be relatively close to a processinglocation which requires printed labels, e.g. a processing location inthe vicinity of hand-held terminal 12-2 in FIG. 12. A base 52F may havea peripheral P3 associated therewith such as a large screen display, aprinter or the like which may supplement the capabilities of a hand-heldterminal, for example printing out new bar code labels at a convenientlocation, or providing a full screen display, rather than the morelimited screen display area of the hand-held terminal 12-2.

If, for example, a base radio 52D which might be located at the ceilinglevel of a warehouse became inoperative at a time when qualified repairpersonnel were not immediately available, with the present system itwould be feasible to provide a substitute base radio or base radios, forexample, as indicated at 52D1 located at table level or the like.

With the present system, the base radio stations do not necessarilyforward data communications received from a given terminal to aparticular host. For example, hand-held terminal 12-2 may request a pathto printer P2, and such a path may be created via base stations 52D1 and52C. Station 52C upon receipt of the message from terminal 12-2 wouldnot transmit the message to a host but would, for example, produce thedesired bar code label by means of printer P2. Further, terminal 12-2may have provision for digitizing a voice message which might, forexample, be addressed to terminal 12-1. The system as illustrated wouldbe operable to automatically establish a suitable path for example, viastations 52D1, 52C, 52B, 52E and 12-1 for the transmission of this voicemessage in digital form. Successive segments of such a voice messagewould be stored, for example, by the terminal 12-1, and when thecomplete message was assembled, the segments would be synthesized into acontinuous voice message for the user of terminal 12-1 e.g. by means ofa speaker 1201 also useful for sending tone signals indicating valid barcode read, etc.

In accordance with the present invention, a hardware system such asillustrated in FIG. 12 may be physically laid out and then upon suitablecommand to one of the network controllers such as 42-2B, the entiresystem would be progressively automatically self-configured forefficient operation. For example, controller 40B could successively tryits communications options with its output ports such as 71-73,determining for example, that host processors were coupled with ports 71and 72, one operating on a 38.4 kilobit per second asynchronous basisand the other presenting a SNA port for the V.35 protocol at 64 kilobitsper second. For example, one host, 42-1B might be a main frame computer,while the other host 42-2B might be a PS/2 type computer system. Thecontroller 40B having thus automatically configured itself so as to becompatible with the devices connected to ports 71 and 72, could proceedto transmit via port 73 a suitable inquiry message to the networkchannel 56. Each of the base stations could operate, for example, on acollision-sense multiple-access basis to respond to the inquiry messagefrom the controller 40B, until each of the successive bases on thenetwork had responded and identified itself. Each base, for example,would have a respective unique address identification which it couldtransmit in response to the inquiry message so as to establish itspresence on the network.

The controller 40B could then transmit auto configure commands to thesuccessive bases in turn, instructing the bases to determine whatperipherals and router bases such as 52D1, 52E and 52F were within therange of such base, and to report back to the controller. For example,bases such as 52C and 52F could determine the nature of peripherals P2and P3 associated therewith so as to be able to respond to an inquiryfrom a terminal such as 12-2 to advise the terminal that a bar codeprinter, for example, was within direct RF range.

In the case of a breakdown of a component of the system such as 52D, itwould merely be necessary to place a router device such as 52D1 at aconvenient location and activate the unit, whereupon the unit could sendout its own broadcast inquiry which, for example, could be answered bythe base stations 52C and 52F, station 52C in turn, advising a relevanthost or hosts of the activation of a substitute router station. Thus,the system is conveniently re-self-configured without the necessity fora technician familiar with the particular configuration procedure. Asanother example, where the base stations are operating utilizing spreadspectrum transmission, the introduction of barriers (such as a new stackof inventory goods) to such transmission between a given base such as52A and various terminals, could result in the base 52A contactingrouter base 52E, for example, with a request to become active withrespect to the blocked terminals.

Description of FIG. 13

FIG. 13 shows an intelligent integrated controller and radio base unit1300 which is integrated into a single housing or case 1301corresponding to the case or housing 20 of FIG. 2. The housing 1301 maybe provided with an external antenna as diagrammatically indicated at1302 with suitable RF coupling to the radio circuitry indicated at 1303.Components 13-70 through 13-74, 13-76, 13-78, 13-96, 13-97, 13-98,13-100, and 13-102 may correspond with the correspondingly numberedconponents described with reference to FIG. 4.

SUPPLEMENTARY DISCUSSION

In accordance with the present disclosure, a network controller, orintegrated network controller and radio unit is coupled to one or morehost computers via a standard interface such as commonly encountered inpractice (e.g. RS232, V.35, Ethernet, token ring, FDDI, and so on). Inthis way, no specialized interface or adapter is required for the host,

Since the preferred network controller can connect to two hosts, if onehost is detected to have failed, or in the event of a system crash, lossof a communication link, or the like, the network controller canautomatically switch to the second host. The second host may be a trulyredundant system, or may be a simpler computer of the PC type (aso-called personal computer) that can simply store transactions untilthe main host is restored. As another example, a single host may have asecond port coupled to a second port of the controller especially if acommunication link failure may be a problem. For example, two ports ofthe network controller may be coupled by separate modems with separatephone lines, leading to separate ports of a single mainframe computer,for example an IBM3090. In a fully redundant system, two ports of anetwork controller may be connected respectively to two mainframecomputers such as the IBM3090.

The disclosed network controller can also connect one radio network totwo hosts using RS232 or V.35 ports or to many hosts using a local areanetwork such as Ethernet, token ring, or FDDI. A number of the disclosednetwork controllers (for example, up to thirty-two) can be connectedtogether to interface many hosts to a single radio network. Thehand-held portable terminals in such a network can then talk to any ofthe hosts they choose.

For example where one port of the disclosed network controller iscoupled via its RS232 interface to a mainframe computer such as theIBM3090, another of its ports may be coupled via an FDDI network with asuper computer e.g. the Cray X-MP. Then mobile and/or portable terminalscan access either the main frame or the super computer, or in general,any of the hosts that are connected to the network controller.

As indicated in FIG. 9, four hosts can be on one network. Referring toFIGS. 10 and 11, a multiplicity of hosts may be coupled with each localarea network so as to be in communication with one or more of thedisclosed network controllers. Furthermore, a single disclosed networkcontroller can control two radio networks such as the one indicated at50 in FIG. 3. Where each network such as 50 is limited to thirty-twodevices, the number of devices is doubled with the use of two radionetworks. Two such radio networks may also be utilized for the sake ofredundancy, with a provision for automatic switch-over from one radionetwork to the second if a problem develops on the first. Two radionetworks may also facilitate the use of different radio technologies inone installation.

The various multi-drop local area networks referred to herein, forexample at 7-82 in FIG. 7 and as represented at 56, 56A, 56B, FIGS. 9through 12, and at 13-82 in FIG. 13 may comprise HDLC based local areanetworks operating at up to 2.5 megabits per second and using biphasespace encoding (FM0) for clock recovery from data.

The components 86 and 94, FIG. 4, and component 13-11, FIG. 13, providesa low-cost base radio interface using three pairs of twisted conductors.One pair provides a bidirectional RS485 data line. Another pair is usedfor the clock and has an RS422 electrical configuration, and is onedirectional from the radio to the controller. The third twisted pair isalso RS422 and is used to communicate from the controller to the radiotransceiver to effect mode selection.

Since it is advantageous to operate the network and router RFtransceiver units so as to be compatible with existing mobile datacollection terminals such as shown in APPENDIX D1 et seq., a preferredmode of operation is based on the RTC protocol as disclosed in theaforementioned incorporated Mahany and Sojka patents and the followingpending applications:

(1) U.S. Ser. No. 07/389,727 filed Aug. 4, 1989, now U.S. Pat. No.5,070,536.

(2) European Published Patent Application EPO 353759 published Feb. 7,1990.

(3) U.S. Ser. No. 07/485,313 filed Feb. 26, 1990, now abandoned.

The disclosures of applications (1), (2) and (3) are hereby incorporatedherein by reference in their entirety.

An aspect of the invention resides in the provision of a networkcontroller having port means selectively configurable for coupling infirst mode with network RF transceiver units at a relatively high datarate such as 100 kilobits per second or higher, and for coupling in asecond mode with network transceiver units at a relatively low data ratesuch as about twenty kilobits per second. Preferably a single port meanssuch as 2, 3 or 5, 6, FIG. 5, can be software configured to interfaceselectively in the first mode or in the second mode. It is presentlyless expensive to use two connectors per port rather than a single37-pin connector for example.

Where a network controller such as 40 operates two high data ratenetworks, for example, one network of RF base transceivers could operatewith the RTC protocol, and the second network could operate according toa different protocol such as that disclosed in pending application Ser.No. 07/660,618 filed on or about Feb. 25, 1991, now abandoned, thedisclosure of which being incorporated herein by reference in itsentirety.

It will be apparent that many modifications and variations may beeffected without departing from the scope of the teachings and conceptsof the present disclosure.

Having described the invention, we claim:
 1. In a data communicationnetwork having a plurality of mobile transceiver units selectivelycommunicative with a plurality of base transceiver units, a method ofautomatically configuring the data communication network, executable bya network controller having a plurality of communication ports,comprising:attempting communication on each of the plurality ofcommunication ports; determining what type of communication protocol isbeing utilized by devices or network channels connected to each of theplurality of communication ports; automatically configuring theplurality of communication ports to be communicatively compatible,according to the determined communication protocol, with devices ornetwork channels connected to each of the plurality of communicationports; transmitting over a network channel connected to one of theplurality of communication ports an inquiry message to the plurality ofbase transceiver units; receiving from the plurality of base transceiverunits a response message indicating an identification of each of theplurality of base transceiver units; transmitting to each of theplurality of base transceiver units auto-configure commands instructingthe base transceiver units to determine what devices such as peripheralsand router bases are within range of each of the plurality of basetransceiver units; and receiving from each of the plurality of basetransceiver units a report of the devices such as peripherals and routerbases that are within range of each of the plurality of base transceiverunits.
 2. In a data communication system comprising a plurality ofmobile transceiver units selectively communicative with a plurality ofbase transceiver units, a control system comprising:switching circuitrythat supports communication among the plurality of mobile transceiverunits via the plurality of base transceiver units; a plurality of hostcomputers coupling with the switching circuitry; and the switchingcircuitry selectively enables communication between the plurality ofhost computers and the plurality of mobile transceiver units.
 3. Thecontrol system of claim 2, wherein communication between the pluralityof host computers and the plurality of mobile transceiver units isselectively enabled to support redundancy.
 4. The control system ofclaim 2, wherein communication between the plurality of host computersand the plurality of mobile transceiver units is selectively enabled inresponse to detected failure of one of the plurality of host computers.5. The control system of claim 2, wherein the switching circuitrycomprises at least one network controller, and wherein the plurality ofhost computers communicate with the plurality of base transceiversthrough multiple communication ports of the at least one networkcontroller.
 6. The control system of claim 5, wherein the multiplecommunication ports of the at least one network controller areautomatically configured by the at least one network controller to becompatible with each of the plurality of host computers.
 7. A datacommunication system comprising:a first wireless transceiver thatparticipates on a first wireless channel to support communication withina cell; a first plurality of wireless devices that participate on thefirst wireless channel; a second wireless transceiver that participateson a second wireless channel to support communication within the cell; asecond plurality of wireless devices that participate on the secondwireless channel; the first and second wireless channels beingcommunicatively incompatible with one another; and a control circuit,communicatively coupled to both the first and second wirelesstransceivers, that supports communication among the first and secondpluralities of wireless devices.
 8. The data communication system ofclaim 7 wherein the first wireless channel supports a different radiotechnology from that supported by the second wireless channel.
 9. Thedata communication system of claim 7 at least one of the first pluralityof wireless devices roams through the cell.
 10. The data communicationsystem of claim 7 further comprising a wired link and a computingdevice, and the control circuit communicatively couples the computingdevice with the first and second pluralities of wireless devices via thewired link.
 11. The data communication system of claim 10 wherein thewired link comprises a wired network.
 12. The data communication systemof claim 10 further comprising a redundant computing device coupled tothe control circuit.
 13. The data communication system of claim 7comprising a third wireless transceiver that participates on a thirdwireless channel to support communication outside of the cell.
 14. Thedata communication system of claim 12 further comprising a remotewireless device, and the third wireless transceiver participates tosupport longer distance communication with the remote wireless devicethan that supported by the first and second wireless transceivers withthe first and second pluralities of wireless devices within the cell.